Apparatus for producing artificial filaments



May 9, 1961 E. K. BAUER APPARATUS FOR PRODUCING ARTIFICIAL FILAMENTS Filed May 12, 1958 A? EE 1 United States Patent APPARATUS FOR PRODUCING ARTIFIC FILAMENTS Ernest K. Bauer, Meadville, Pa., assignor to American Viscose Corporation, Philadelphia, Pa., a corporation of Delaware 7 Filed Ma 12, 1958, Ser. No. 734,717 7 Claims. 01. 137-567) The present invention relates to a system or apparatus for producing artificial filaments and more particularly, artificial filaments having alternating segments of differing characteristics such as difierent colors.

Among the conditions afiecting the denier of artificial filaments is the pressure and volume of flow of the spinstant flow of a spinning solution of a particular color or other characteristic and periodically adding to the basic spinning solution a second solution which imparts a different color or characteristic to the material extruded through the spinneret orifices, and during the periods while the second solution is being added there is an increased flow through the orifices with the result that the filaments are characterized by alternating segments of varied cross-section. For example, when spinning filaments of alternating white and red segments, the red segments will generally have a greater cross-sectional area than the white segments because of the addition of the red dye to the normal flow of the white spinning solu tion. Another difiiculty encountered in spinning filaments having alternating segments of differing characteristics has been the inability to provide sharp lines of demarcation between the segments. 7

It is an object of the present invention to provide an apparatus for spinning constant denier filaments having alternating segments of difiering characteristics such as difierent colors.

It is a further object of the invention to provide an apparatus for spinning filaments of the type referred to wherein by proper manipulation of the apparatus either sharp lines of demarcation may be provided between the alternating segments or a zone may be provided between the alternating segments characterized by a mixture of the components of the alternating segments, that is, to say, in the case of different colors there may be a sharp line of demarcation between the colors or there may be a substantial zone between the two colors comprised of a mixture of the two colors.

Other and further objects, features and advantages of the invention will become apparent as a description of a preferred embodiment thereof proceeds.

Referring now to the drawings:

Figure 1 is a diagrammatic showing of the system of the present invention, and

Figure 2 is an elevational view of a device employed for controlling the operation of the two pumps forming a part of the system.

Two differently colored or otherwise differently characterized supplies of spinning solutions or dopes are contained in the tanks 10 and 11 from which they are pumped respectively through conduits 12 and 13 for extrusion through a common spinneret or jet 14 connected by a relatively short length of pipe 15 to the two conduits. .The spinning solutions may be viscose, acetate or any other solutions which may be spun by wet or dry spinning methods to form filaments. The conduits 12 and 13 may contain filters 16 and 17, respectively, such as ordinarily employed in heretofore known spinning systems.

In the ordinary case, when spinning filaments from a single solution,.a positive displacement pump, such as a gear pump, is provided in the line at a point close to the tion to the ordinary difierential found in an automobile.

The driving gear of the ditierentialis driven by a sprocket chain 25 from a sprocket wheel 26 provided on the output shaft of a speed reduction unit 27, the input of which may be driven from any suitable constant speed motor 28.

As previously mentioned, among the conditions afiecting the denier of the filaments formed by extrusion of the spinning solution through the spinneret is the pressureand volume of flow of the spinning solution. Since the present invention contemplates the production of filaments having a constant denier or cross-sectional area throughout their length, means is provided for continuously supplying the spinneret with a constant volume and pressure of spinning solution. Since the two pumps 18,

and 19 are driven from a diiferential gear, when one of said pumps is stopped the other one will bedriven at twice the speed at which it would be driven were the two pumps being operated simultaneously. This, of course, is characteristic of a difierential gear drive.

In order to stop the two pumps 18 and 19 alternately,- positive brake means are provided in the form of teeth 29' and 30 formed on the ends of a common rocker arm 31 pivotally mounted at 32. The rocker arm 31 may be rocked by means of a solenoid 33, the armature of which is connected to said rocker arm so that when said solenoid is energized the rocker arm is rocked to engage the tooth 29 with the drive gear 20 and upon de-energization said solenoid rocks the rocker arm in the opposite direction to engage the tooth 30 with the drive gear 21. In practice, the gears 20 and 21 are driven at a fairly low speed so that it is entirely practicable to provide a positive brake of this type.

If the two pumps 18 and 19 were allowed to operate simultaneously without any braking action upon either of them, equal amounts of the spinning dopes from tanks 10 and 11 would be supplied to the. spinneret and in the event that the two dopes were of different colors, the

tem of this invention the two pumps are never allowed to' operate at the same time, but when one of them is stopped the difierential gear immediately delivers its full power to the other pump and thus there always be a particular quantity of spinning solution supplied to the spin- Patented May 9, 1961 3 neret, the supply consisting alternately of one or the other of the difierently characterized spinning solutions. When the stopping of the pumps is abrupt as is the case with a positive type brake, the resultant filaments have a sharpline of demarcation" between the difierently characterized segments.

In the event that it is desired to produce constant denier filaments having alternating segments of diflering characteristics connected by zones wherein the filaments have a mixture of characteristics, a friction brake will be provided instead of the positive brake so that it is possible to stop the pumps gradually instead of abruptly. In this instance the one pump will be speeded up by the differential gear 24 in direct proportion to the slowing down of the other so that during the period while both pumps are operating, some of each of the spinning dopes will be. supplied to the spinneret to thus produce between the segments of difiering characteristics a zone consisting of a mixture, but nevertheless of the same denier.

In order to automatically produce filaments having alternating segments of the same length, the output shaft of the speed reduction unit 27 carries a cam 34 having one-half of its periphery of a different radius from the other half and this cam cooperates with a follower 35 provided on the operating arm of a micro switch 36 connected in a circuit including'the solenoid 33. The switch 36 may be so arranged as to cause energization of the solenoid either when the follower 35 is on the high or low portion of the periphery of the cam 34 and de-,

energized when said follower is on the other portion of said cam to thus rock the rocker arm 31in first one direction and then the other to alternately stop or slow down the pumps 18 and 19.

' Having thus described a preferred embodiment of the invention, what is claimed is:

1. In an apparatus for spinning constant denier filaments having alternating segments of difiering character istics, two spinning dope supplies of difiering characteristics, a conduit leading from each dope supply to a common outlet, a positive displacement pump in each of said conduits for pumping the spinning dopes under pressure through said conduits, a difierentialdrive for said pumps, a motor for driving said diiferential drive, brakes for said pumps, means for alternately operating said brakes, said difierential drive speeding up one pump in direct proportion to the slowing down of the other whereby spinning dope will be supplied to the outlet at a constant rate.

2. Apparatus for spinning constant. denier filaments havingalternating segments of difiering characteristics comprising two spinning dope supplies of differing .characteristics, a conduit leading from each dope supply to a common outlet, a positive displacement pump in each of said conduits for supplying pressure to the spinning dopes, said pumps being of the same capacity, a diflerential gear drive for said pumps, and means for alternately interrupting the operationof said pumps, said. differential drive increasing the speed of the operating pump when the other pump is stopped whereby the total supply of spinning dope to the outlet remains constant.

3. Apparatus for spinning constant denier filaments having alternating segments of differing characteristics comprising two spinning dope supplies of diifering charaeteristics, a conduit leading from each dope supply to a common outlet, a positive displacement pump in each of said conduits for pumping the spinning dopes under pressure through said conduits, said pumps being of the same capacity, a difierential gear drive for said pumps, a motor for driving said difierential gear, brake means for stopping said pumps alternately, and meansoperable by said motor for operating said brake means.

4. Apparatus for spinning constant denier filaments av n a r a n segments o e i a a t s s with a substantial zone of difiusion therebetween pom: prising two spinning dope supplies of differing character- Y 4 istics, a conduit leading from each dope supply to a common outlet, a positive displacement pump in each of said conduits for pumping the spinning dopes under pressure through said conduits, a difierential gear drive for said pumps, a motor for driving said difierential gear, brake means for said pumps, a rocker arm for alternately operating said brake means, means to rock saidrocker arm in one direction to operate one of said brake means and means to rock said rocker arm in the opposite direction to operate the other brake, means.

5. Apparatus for spinning constant denier filaments having alternating segments of differing characteristics 7 comprising two spinning dope supplies of differing characteristics, a conduit leading from each dope supply to a common outlet, a positive displacement pump in each of said conduits for pumping the spinning dopes under pressure through said conduits, said pumps being of the same capacity, a differential gear drive for said pumps, a motor for driving said difierential gear, cam means driven by said motor, switch means operated by said cam means,

a solenoid in a circuit including said switch means,

means operable. by said solenoid upon energization there'- of due to closing of said switch to stop one of said pumps, and means operable upon de-energization of said solenoid for stopping the other of said pumps, said diflerential gear drive maintaining a uniform flow of spinning dope to the common outlet.

6. Apparatus for spinning constant denier filaments having alternating segments of dilfering characteristics comprising two spinning dope supplies of difiering characteristics, a conduit leading from each dope supply to a common outlet, a positive displacement pump in each 7 of said conduits for pumping the spinning dopes under pressure through said conduits, said pumps being of the same capacity, a difierential gear drive for said pumps, a motor for driving said differential gear, brake means for stopping saidpumps, a rocker arm for alternately operating said brake means, a solenoid operable upon energization to rock said rocker. arm in one direction to operate oneof said brake means and stop. one of said pumps and operable upon de-energization to rock said rocker arm in the opposite direction to operate the other brake means and stop the other pump, n electric circuit for said solenoid including a switch, and means operable by said motor for operating said switch.

7. Apparatus for spinning constant denier filaments having alternating segments of difiering characteristics comprising two spinning dope supplies of difiering characteristics, a conduit leading from each dope supply to a common outlet, a positive displacement pump in each of said conduits for pumping the spinning dopes under pressure through said conduits, said pumps being of the.

same capacity, a differential gear drive forsaid pumps, a motor for driving said difierential gear, brake means for stopping said pumps, a rocker arm "for alternately operating said brake means, a solenoid operable upon energization to rock saidrocker arm in one direction to operate one of said brake means and stop one of said pumps and operable upon de-energigation to rock said rocker arm in the opposite direction to operate the other brake means and stop the other pump, an electric circuit for said solenoid including a switch, rotary cam means for operating said switch, said cam means being driven by said motor and serving to maintain said switch closed during one-half its revolution and permitting said switch to open during the other half. 7 i r References Cited in the file of this patent UNITED STATES PATENTS I Bryson Dec. 25, 1934 

